Four-year longitudinal study of mandibular dysfunction in children.

A longitudinal study of clinical signs and subjective symptoms of mandibular dysfunction was performed with a 4-yr interval in 119 children, now 11 and 15 yr old. The results showed that 66% in both age groups had clinical signs while 62 and 66%, respectively, complained of subjective symptoms. In most cases the signs were mild, but 11% of the 11-yr-olds and 17% of the 15-yr-olds had moderate, or, in a few cases, severe signs of dysfunction. Most of the children with subjective symptoms had their symptoms occasionally but 3% in the younger and 11% in the older age group had frequent symptoms from the masticatory system. When comparisons were made with the findings 4 yr earlier, it was noted that the subjective symptoms had increased in frequency in the younger children, while the clinical signs had increased in both groups. These age differences, as well as the prevalence figures recorded longitudinally, agreed well with previous findings in cross-sectional investigations of different age groups.